Design concept for a very easily and cheaply constructable greenhouse, principally for use in urban settings.
(And a non electrical cooling system to reduce heat build up and frosts in growing spaces).

Thursday, 15 September 2011

Last month's been spent in Ireland, wwoofing on a pretty decent community called The Hollies and spending time with some good friends from Scotland.

As of yesterday tho I've arrived in Leipzig, former East Germany, for the dual purpose of prototyping a couple solar energy ideas (check http://solarflower.blogspot.com for updates) and just seeing what's going on here.
So far, it seems; a lot.

I'm staying with a friend, who informs me that to buy the entire building her flat's in would set you back about €40k, with something less renovated being about half that, and less still at auction. If you come to the city with a business idea the council will offer you free office and work space. Most streets I'd say about a third to a half of the buildings have been abandoned for decades. The main commercial street near here is two thirds empty, and it remains the commercial strip because it's doing so well in having any at all.

And that's why so many people have started coming here. If you want to get a project off the ground, or try something new and need workspace, or want to build a community, Leipzig will let you, and for free.

With regards to urban farming I'm not yet sure how much is happening. There's large number of allotments around the city, but judging by them being almost entirely lawn and flowers, I'm thinking the average age of ownership would be edging up on the average life expectancy.

Saturday, 30 July 2011

We lost the location, Ecobox, due to last minute skittishness on matters of council and landowner permission, budget, and various other things. As I'm heading to Ireland in about a week, and I don't get the sense that there's such a groundswell of will to see this thing through here, might as well call it.
We also had a few troubles lining up materials, as Paris just inexplicably lacks certain things, like greenhouse plastic. But we had a few leads and probably would've got it sorted this week.

So that's that then. I'm going to talk to some people in Cork when I arrive, there's a fairly well established permaculture school there and maybe a bit more interest than here.
But this was always more of an experiment / temperature check than a project I was determined to see through. I simply don't yet know how viable this kind of approach to food production is in Europe and other Western countries. It won't happen until there's the will to do it, and I have doubts that currently there is. When I'm in more developing countries I imagine the dynamic will be somewhat different.
Mind you, this is Paris. If I'd really wanted to give this thing its best chance I would've gone to Copenhagen or Berlin. But I just wanted to hang out in Paris for the summer.
And now Ireland.
I'll keep you posted.

I've met permaculturalists, guerilla gardeners, squatters, the Zeitgeist movement, urban farmers, artists, engineers, transition towners, and everyone else in Paris there is to meet.
This is now an open call for participants in building the first greenhouse, to be finished by early August. We have a good location, money and materials are basic, we just need people.
When I get at least four names I'll call the fist meeting, and we'll begin.

Monday, 4 July 2011

Went to Ecobox's permaculture fair yesterday, talked to some people involved in the scene, got some advice and expressions of interest. Hopefully meeting some guerilla gardeners this week, will let yall know about where and when, if you wanted to attend.

Also been talking briefly with a girl who's been involved with urban farming in the states, says in Detroit, Philadelphia and New York especially there's quite a scene going. So hopefully whatever we develop here can be of help. No one seems to be following the mobile greenhouse model, no real idea why...

And.. talked to a dude involved in the local Zeitgeist Movement, who reckons they've been talking up the idea of urban hydroponics for a while now, so hopefully can tie in with them as well.

Tuesday, 28 June 2011

The lot is being used by the Ecobox community garden, and they seem pretty interested in the project.Not a problem that it's asphalt as we'll be coming up off the ground with raised beds, shelves etc. I have serious reservations about planting in city soil anyway, due to heavy metals and other toxins. We'll be making our own, probably through a combination of compost, manure, a trailer full of dirt from outside the city, and possibly even a bio-digester.The only issue with it being a solid surface is not being able to sink a cooling system, which after the last two freakishly hot days here in Paris (up to 38 C), is starting to look like an important addition. There is, however, a grassy bank just over that fence, so I'm thinking to put the water tank in that and just run the hoses to it.Now just need to start building...

Approach the land owners saying we'll be gone the day they say to be, we won't leave a mark and might be able to pay a little rent.

Build several greenhouses and other useful things.Farm Paris.

This isn't for demonstration purposes or raising awareness etc, this is to grow large quantities of good food year round. When we inevitably get moved on from a block, pack everything up and shift to the next. The only limiting factors are how much land we'd have access to and how many people are involved. All tech and infrastructure will be open source and hopefully we'll get copied.

Other potential projects to build in:

Free permaculture university (PDCs do not need to be that expensive)

Open circus/juggling/parkour/graff space (plants like CO2, I like aerialist silks)

Energy and water production (might as well testbed some stuff while we're here)

Stick a fork in it, it's done.Well, few finishing touches; maybe some double sided flooring tape to lock down the edges, and of course all the shelving to go in, but that's the structure wrapped and roofed.Dimensions:9 meter triangle side3.8 meters tall100 square meters of plastic35 square meter footprint

~100 square meters growing space, depending how you use it.

Total cost:NZ$120/€68($95 for the plastic, about $25 for screws, nails, etc. All wood felled or recycled).

Took three of us about 7 days to build, not including getting the materials together, but it would've been about half that if we hadn't been inventing the thing as we went.

Next one will be done slightly differently, bit easier to construct but generally the same. Maybe a third larger...

Wednesday, 15 June 2011

Hey, got a hundred and fifty hits yesterday, that aint bad. I think largely due to this writeup here.

Writing this from the Hong Kong international airport, gate 65. Arriving Germany (tomorrow?) and making a bee line for Paris. Got a place to stay last minute through Couchsurfing.God I'm tired. (3 am biological time, been awake since 6 am (this??) morning, am now just over halfway through this trip with another twelve hour flight to go.)

Monday, 13 June 2011

Back now in Christchurch being rocked by fairly constant aftershocks, flying out tomorrow for Europe from one volcanic ash cloud to another. Yeesh.

My father's currently putting the final touches on the greenhouse, I didn't quite have time to do so myself, and he'll be sending down some photos soon which I'll post here.

I was planning to be travelling Europe this summer roadtrip style with the solarflower project, but that has now fallen through due to lack of funds. Got another idea tho, and will post it here shortly. Think you might like it...

Thursday, 9 June 2011

Two days later the things still just a smidge off completion. I was supposed to leave for Christchurch this morning (well, yesterday, officially), now looks to be tomorrow noonish due to some on-the-fly redesigns of this structure taking more time than thought.But it's looking pretty sweet. Photos tomorrow for sure.

Sunday, 5 June 2011

Didn't think to take a better photo than this, but you can see that the floors are in. Tomorrow we start wrapping the whole thing, which we'll need to finish in good time coz I'm away on Wednesday and Tuesday looks like rain.

Thursday, 2 June 2011

All the materials are now in place, by end of tomorrow I want to have the other two tripods up and floored. Wrapping and roofing to follow, tho I'm out of here in less than a week now, so it's going to have to be quick.

Sunday, 22 May 2011

Super quick note to let you know that we're about halfway through actually building the first greenhouse out here at the Rainbow Valley community in Golden Bay, New Zealand.Got a bunch of photos etc which will be going up as I get around to it.

Wednesday, 30 March 2011

A few photos of the setup:

20 litre oil drum, grabbed from a skip behind a car servicing centre. Hose and fittings bought new, can be a bit pricey, but Western Australia's a bit ridiculous price wise since they got rid of their manufacturing base.

Luckily the windows at my mum's place are pretty badly fitted, so there was a gap big enough to get the hoses through.Just above is the car port, so the bank is shaded throughout the day. This seems to be important.

The very ghetto air pump housing. Taken from a old vacuum cleaner, stuck in some tupperware. Worked fairly well minus the fact that whatever plastic that is just does not want to adhere to any kind of glue, at all. Hence the tape and string, and it still leaked a bit.Close enough is good enough.

Actually got all this last week, but most of it was being gathered on the day I was flying out of Australia, so was gathered while running round packing, and this is the first chance I've had to get it down properly.

I did two basic experiments.

1.

Filled the 20 litre drum (30 cm tall, deepest point 1.1 m, shallowest 80 cm, in dry sand over sandstone) with hot water. This was in the form of 3 x 7 litres bought to boiling on the stove and poured into the tank through the connector hose. Should've measured the water temp at start and end of filling (took a minute or two to get it through the funnel) but I'm going to assume it was about 90 C. The ground temp was around 24.5 C.

So:

First 7 L volume at 9.40 am, second at 9.57, third at 10.12. Measured tank temp at 10.15 and was 77 C. This is a total of just on 5.75 mega joules.

Full data:

time water temp (C)

10:15

77

10:30

74

10:50

70

11:05

67

11:20

65

11:30

64

11:45

63

12:00

60

12:15

59

12:35

57

12:45

56

13:00

56

13:40

53

14:00

52

14:30

50

15:00

48

15:35

46

16:35

43

17:00

43

17:45

41

18:45

39

20:00

38

21:00

36

23:20

34

00:15

33

08:20

29

11:25

28

13:15

28

14:00

28

16:00

27

17:15

27

18:30

27

23:35

26

08:45

25

Graph!

And 2:

More relevant to the actual cooling system, I plugged the whole thing together and ran it for about 8 hours. The setup was: air being sucked from the top of the house through about 9 meters of 18mm garden hose into the air pump housing, which was a vacuum cleaner pump and motor inside a tupperware container with the attached electronics.

This meant the air was passed over the motor itself, which added a lot of heat to it. Dumb for a proper installation, but good for fully testing the system.

Air flow was about 2 litres / second, in that it took 20 seconds to fill a 40 litre bag.

The air then passed through 3 m hose, bubbled through about 30 cm vertical of water, and exited into the house through another 3 meters hose.

Air In

Air Out

Air House

11:15

50

24

30

11:30

52

24.5

30

12:05

54

24.5

31

12:40

53.5

24

32

13:25

55.5

24

29

14:40

50

24.5

28

15:20

49

24.5

27

16:20

46

25

26

17:05

48

24.5

26

19:10

45.5

24.5

25

'Air in' being the temp coming out of the hose from the pump, ie just before it enters the tank. Pretty high due to the motor, the general air temp was about 34-36.

Air out is the air coming directly out of the tank.

Air house is the what came out into the house. At about 13:00 I wrapped the whole last length of hose in insulant and moved it out of the sun. I was surprised by how much heat the air picked up through only a couple meters of rubber hose, but there you go.

So I guess the two most striking things are that even with a fairly basic interface between the air and water (vague attempt at a diffuser, not really) the air dropped all it's heat, even at 55 C.

And that even with only 20 litres of water, which was only ever meant as a quick test, the water temp didn't really come up over the ground temp. True that 2 litres of air per second isn't much (I could've turned the motor up a lot more, but didn't want to 'splode it) but at an average of 50 C, the air was twice the temp above 24 that it would probably usually be running, so is therefor the same energy as 37 C at 4 litres per second, which is quick enough to replace 50 cubic metes of air in about 3.5 hours.

Monday, 17 January 2011

To check the ground temp for the previously mentioned cooling system I rigged up a simple temperature probe consisting of a meter length of garden hose taped to a stick (to keep it straight) and plugged at the bottom end. I buried this to a depth of about 90 cm (3 feet, as far as my arm can reach into the ground), put in a small amount of water for conductivity, and lowered in a glass thermometer on a thread. I then plugged the open end of the hose to prevent air exchange.Every so often I pull out the thermometer and record the ground and air temperatures.The ground is dry sand on a 45 degree incline, shaded throughout the day. Initially I measured a spot beside the house which got direct sun most of the day, and it was about 7 C hotter

Results:

Ground (C)

Air (C)

January 14th

14.24

22

21.5

22.30

22

22

Jan 15th

10.10

21

26

12.00

21.5

26

14.00

21.5

25

17.15

21.5

24

Jan 16th

8.30

21

25

13.30

21.5

35.5

15.15

21.5

30

16.45

21.5

23.00

21

22

Jan 17th

10.45

21

29.5

Jan 24th

09.00

21.5

18

This shows that even an air temp of 35.5 C (96 F) doesn't affect the ground temperature at that depth at all, making this cooling system potentially quite viable.

Once I get a chance (after the solar device is going) I'll take a crack at piecing this together.

Mild update: overnight temperature went down to 13 at about 3.30 am, but ground temp measured at 9.15 am hadn't budged 0ff 21.5. At this point I'm going to call this conclusive.

Nother update; ground temp is up to a steady 23, so guess there's seasonal variation. February is generally the hottest month round here.

Update the third; I suspect the increase may be due to the sun shifting on to it as it gets lower in the sky. Also have had an air temp of 38 C, ground temp unaffected.

Update IV; had a cloudy day, and the temperature was still 23, so if that's due to increased direct sunlight, it's at least a couple days averaged. In other news the ground temp has now gone up to 24, the maximum air temp has been 39.5, and the probe has been removed to make way for the cooling tank as I actually make this thing.A 1.5 meter deep hole involves more digging that you'd think...